Zero-fluoroscopic simultaneous catheter ablation of the atrioventricular node re-entry tachycardia and the supraventricular tachycardia from crista terminalis. Case report

Introduction. Atrioventricular nodal reentrant tachycardia (AVNRT) is the most common paroxysmal supraventricular arrhythmia in adults, accounting for up to 60% of all supraventricular tachyarrhythmias (SVT). The first-line treatment for symptomatic recurrent AVNRT is catheter ablation (CA). Performance of CA with zero-fluoroscopy (ZF) using three-dimensional (3D) electroanatomical mapping systems is both possible and safe. Brief description. This article presents a clinical case of successful catheter ablation of right atrial supraventricular tachycardias (AVNRT and atrial tachycardia (AT) originating from the crista terminalis). All stages of the procedure were performed using CARTO 3D electroanatomical mapping (Biosense Webster Inc., USA) with a QDOT MICRO irrigated ablation mapping electrode (Biosense Webster Inc., USA) under (ZF). The first stage involved ablation of the slow pathways of the atrioventricular junction. The second stage involved ablation of a AT wave with a cycle duration (cd) of 456 ms and a right-sided activation front. We made a voltage and activation map of the right atrium, taking into account the morphology and activation pattern of the atrial component along the coronary sinus and the right atrium. Analysis of the activation map shows that the early activation zone on the SVT with a depolarisation time of 456 ms is located in the middle third of the crista terminalis. In this zone, areas of fibrotic changes in the myocardium are recorded according to the voltage map. A series of RF ablations was performed in the zone of interest, with the AT stopped at the moment of ablation, the ECG showed sustained sinus tachycardia at 92 beats per minute. Discussion. Three-dimensional electroanatomical mapping systems enable the creation of a «digital» twin of the patient’s heart, which allows for the accurate reproduction of the interrelationships between the heart’s anatomical structures. According to the findings of a number of studies and as demonstrated by our clinical case, there is no evidence to support the benefits of performing catheter ablation of right atrial SVTs under constant fluoroscopy. Conclusion. According to the findings of a number of studies and as demonstrated by our clinical case, there is no rationale for performing catheter ablation of right atrial supraventricular tachycardia under constant fluoroscopy.